KR20150069084A - Pump tower structure of lng cargo tank - Google Patents

Pump tower structure of lng cargo tank Download PDF

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Publication number
KR20150069084A
KR20150069084A KR1020130154888A KR20130154888A KR20150069084A KR 20150069084 A KR20150069084 A KR 20150069084A KR 1020130154888 A KR1020130154888 A KR 1020130154888A KR 20130154888 A KR20130154888 A KR 20130154888A KR 20150069084 A KR20150069084 A KR 20150069084A
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KR
South Korea
Prior art keywords
lng
pipe
storage tank
pump tower
pump
Prior art date
Application number
KR1020130154888A
Other languages
Korean (ko)
Inventor
안윤남
김도현
김정훈
이철호
정태석
Original Assignee
에스티엑스조선해양 주식회사
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by 에스티엑스조선해양 주식회사 filed Critical 에스티엑스조선해양 주식회사
Priority to KR1020130154888A priority Critical patent/KR20150069084A/en
Publication of KR20150069084A publication Critical patent/KR20150069084A/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B25/00—Load-accommodating arrangements, e.g. stowing, trimming; Vessels characterised thereby
    • B63B25/02—Load-accommodating arrangements, e.g. stowing, trimming; Vessels characterised thereby for bulk goods
    • B63B25/08—Load-accommodating arrangements, e.g. stowing, trimming; Vessels characterised thereby for bulk goods fluid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B27/00—Arrangement of ship-based loading or unloading equipment for cargo or passengers
    • B63B27/24—Arrangement of ship-based loading or unloading equipment for cargo or passengers of pipe-lines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B27/00—Arrangement of ship-based loading or unloading equipment for cargo or passengers
    • B63B27/30—Arrangement of ship-based loading or unloading equipment for transfer at sea between ships or between ships and off-shore structures
    • B63B27/34—Arrangement of ship-based loading or unloading equipment for transfer at sea between ships or between ships and off-shore structures using pipe-lines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
    • B65D90/00—Component parts, details or accessories for large containers
    • B65D90/52—Anti-slosh devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B67—OPENING, CLOSING OR CLEANING BOTTLES, JARS OR SIMILAR CONTAINERS; LIQUID HANDLING
    • B67D—DISPENSING, DELIVERING OR TRANSFERRING LIQUIDS, NOT OTHERWISE PROVIDED FOR
    • B67D9/00—Apparatus or devices for transferring liquids when loading or unloading ships
    • B67D9/02—Apparatus or devices for transferring liquids when loading or unloading ships using articulated pipes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2221/00—Handled fluid, in particular type of fluid
    • F17C2221/03—Mixtures
    • F17C2221/032—Hydrocarbons
    • F17C2221/033—Methane, e.g. natural gas, CNG, LNG, GNL, GNC, PLNG
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
    • F17C2223/01—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the phase
    • F17C2223/0146—Two-phase
    • F17C2223/0153—Liquefied gas, e.g. LPG, GPL
    • F17C2223/0161—Liquefied gas, e.g. LPG, GPL cryogenic, e.g. LNG, GNL, PLNG
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2225/00—Handled fluid after transfer, i.e. state of fluid after transfer from the vessel
    • F17C2225/01—Handled fluid after transfer, i.e. state of fluid after transfer from the vessel characterised by the phase
    • F17C2225/0146—Two-phase
    • F17C2225/0153—Liquefied gas, e.g. LPG, GPL
    • F17C2225/0161—Liquefied gas, e.g. LPG, GPL cryogenic, e.g. LNG, GNL, PLNG
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2227/00—Transfer of fluids, i.e. method or means for transferring the fluid; Heat exchange with the fluid
    • F17C2227/01—Propulsion of the fluid
    • F17C2227/0128—Propulsion of the fluid with pumps or compressors
    • F17C2227/0135—Pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2260/00—Purposes of gas storage and gas handling
    • F17C2260/01—Improving mechanical properties or manufacturing
    • F17C2260/016—Preventing slosh
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
    • F17C2270/00—Applications
    • F17C2270/01—Applications for fluid transport or storage
    • F17C2270/0102—Applications for fluid transport or storage on or in the water
    • F17C2270/0105—Ships

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Filling Or Discharging Of Gas Storage Vessels (AREA)

Abstract

The present invention relates to a pump tower structure for an LNG storage tank. A pipe having an elliptical cross-sectional shape comprises: a supply pipe to supply an LNG to the inside of a storage tank; a pair of discharge pipes discharging the LNG stored inside the storage tank to the outside; and an emergency pipe connected to the discharge pipe and discharging the LNG stored inside the storage tank to the outside when a main pump supplying the LNG to the discharge pipe is broken down.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a pump tower structure for an LNG storage tank,

The present invention relates to a pump tower structure of an LNG storage tank, and more particularly, to a pump tower structure of a LNG storage tank, and more particularly, to a pump tower structure of a LNG storage tank (LNG- To a pump tower structure of an LNG storage tank for loading or unloading LNG.

In general, natural gas is transported in a gaseous state through land or sea gas pipelines, or is transported to a distant consumer where it is stored in an LNG carrier in the form of liquefied natural gas (hereinafter referred to as LNG).

The LNG is obtained by cooling the natural gas to a cryogenic temperature (approximately -163 ° C), and its volume is reduced to approximately 1/600 of that of the natural gas in the gaseous state, making it well suited for long distance transportation through the sea.

LNG carriers that carry LNGs to the sea, and LNG carriers to unload LNGs to landfill sites, or LNG RVs (LNG carriers) that transport LNGs to the sea, Regasification Vessel contains a cryogenic storage tank (often referred to as a 'cargo hold') of liquefied natural gas.

In recent years, demand for floating floating structures such as LNG FPSO (Floating, Production, Storage and Offloading) and LNG FSRU (Floating Storage and Regasification Unit) has been increasing steadily. LNG carrier or LNG RV And a storage tank to be installed.

LNG FPSO is a floating marine structure that is used to liquefy natural gas produced directly from the sea and store it in a storage tank and, if necessary, to transfer the LNG stored in this storage tank to an LNG carrier. In addition, the LNG FSRU is a floating type of floating structure that stores LNG unloaded from LNG carriers in offshore sea, stores it in a storage tank, vaporizes LNG if necessary, and supplies the LNG to the customer.

In this way, a storage tank for storing LNG in a cryogenic condition is installed in a marine structure such as an LNG carrier, LNG RV, LNG FPSO, and LNG FSRU that transports or stores a liquid cargo such as LNG.

The LNG storage tank may be classified into an independent type and a membrane type.

Typically, the membrane type storage tanks are divided into GTT NO 96, Mark III and CS1, and the independent storage tanks are divided into MOSS type and SPB type.

The membrane type LNG storage tank has a pump tower for loading or unloading LNG. Since the membrane type LNG storage tank is weak in structural rigidity, when the ship moves in the sea condition, a liquid such as LNG The structural damage of the pump tower installed in the storage tank is expected because it is inevitably more vulnerable to the sloshing problem in which the material flows.

Therefore, an example of an LNG storage tank for preventing the structural damage of the pump tower is disclosed in Korean Patent Laid-Open Publication No. 2012-0077627 (hereinafter referred to as "prior art").

1, the conventional art includes a loading pipe 24 for loading LNG into the cargo tank 10, a discharge pipe 21, 22 for discharging the LNG stored in the cargo tank 10, A main pump connected to the discharge pipes 21 and 22 for supplying the LNG to the discharge pipes 21 and 22; and a discharge pump for discharging the LNG stored in the cargo tank 10 when the main pump fails (23) and at least one sampling pipe (50) for checking the components of the gas remaining in the cargo tank (23), the pump tower .

However, since the sectional shape of the pump tower is formed in a circular cross-section, the hydraulic structure of the pump tower is very high due to the influence of the sloshing as described above, resulting in a very weak structural rigidity. .

Korean Patent Publication No. 2012-0077627 (Jul. 10, 2012)

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a pump tower that can improve the cross-sectional shape of a pipeline provided in a pump tower, So that the load can be reduced.

According to another aspect of the present invention, there is provided a pump tower structure for an LNG storage tank, including a supply pipe for supplying LNG into a storage tank, a pair of discharge pipes for discharging the LNG stored in the storage tank to the outside, And an emergency pipe connected to the discharge pipe for discharging the LNG stored in the storage tank when the main pump fails to supply the LNG to the discharge pipe is formed in an elliptical cross-sectional shape elongated in the width direction of the ship .

According to the present invention, a reinforcing material passing through the center of the pipe is installed inside the pipe.

And the reinforcing member is provided on the inner surface of the pipe having the shortest diameter.

According to the pump tower structure of the LNG storage tank according to the present invention having the above-described structure, the pipe structure provided in the pump tower is formed into an elliptical cross-sectional shape to reduce the drag coefficient, There is an effect that the load generated by the flow can be reduced.

1 is a cross-sectional view showing an arrangement of a pump tower structure according to the prior art.
2 is a schematic perspective view showing an LNG storage tank having a pump tower according to the present invention.
3 is a plan sectional view showing a pump tower structure of an LNG storage tank according to the present invention.
4 is a graph showing a change in drag force of the pump tower structure of the LNG storage tank according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 4. FIG.

FIG. 2 is a schematic perspective view illustrating an LNG storage tank having a pump tower according to the present invention. The pump tower 100 according to the embodiment of the present invention includes a gas carrier for transporting or storing LNG, Is installed in the storage tank T for loading or unloading LNG into a storage tank T such as an LNG-RNG-LNG-FSRU and an LNG-recharged ship LNG-RV.

2, the pump tower 100 includes a filling pipe 210 for supplying LNG into the storage tank T and a filling pipe 210 for supplying the LNG stored in the storage tank T to the outside And a main pump (not shown) connected to the discharge pipe 220 for supplying LNG to the discharge pipe 220. The LNG storage tank 220 is connected to the discharge pipe 220, And an emergency pipe 230 for discharging the water to the outside.

The pump tower 100 constructed as described above is disposed in a triangular configuration in which a pair of discharge pipes 220 and the emergency pipe 230 each occupy one corner so as to have a stable structure.

The supply pipe 210 is disposed adjacent to the emergency pipe 230.

The supply pipe 210 is connected to an external loading device to load the LNG into the storage tank T and the discharge pipe 220 is connected to an external unloading device T) to the outside.

The main pump is installed at a lower portion of the discharge pipe 220 to supply LNG to the discharge pipe 220. The LNG supplied to the discharge pipe 220 is discharged to the outside through the discharge pipe 220.

The emergency pipe 230 is provided to replace the discharge pipe 220 when the main pump fails. An emergency pump (not shown) is installed below the emergency pipe 230, and when the main pump fails The emergency pump operates to discharge the LNG stored in the storage tank T to the outside.

The pump tower 100 is provided with a ladder 300 for maintenance, a foot plate 400 and a connecting member (not shown) for connecting and fixing the pipes 200 to each other in addition to the piping 200 for loading and unloading LNG 500), and various electric cableways (not shown).

The pump tower 100 constructed as described above increases the load acting on the pump tower 100 as the flow rate of the fluid increases and the drag coefficient increases as the LNG in the storage tank T sloshing. The invention has a point of reducing the drag coefficient determined by the cross-sectional shape of the pump tower 100 in order to reduce the load acting on the pump tower 100.

Accordingly, the cross-sectional shape of the pipe 200 such as the supply pipe 210, the discharge pipe 220 and the emergency pipe 230 of the pump tower 100 according to the present invention is formed into an elliptic shape having a relatively lower drag coefficient than a circular shape .

At this time, it is preferable that the elliptical cross-sectional shape is formed to extend in the width direction of the ship so that the drag coefficient can be lowered relative to the sloshing direction of a general ship.

FIG. 4 is a graph showing a change in drag force of a pump tower structure of an LNG storage tank according to the present invention. When a cross-sectional shape of a pipe 200 installed in a pump tower 100 changes from a circular shape to an elliptical shape, Indicating a significant decrease.

4, D represents the vertical diameter of the pipe 200, I represents the transverse diameter of the pipe 200, and C D represents the drag coefficient. As the circular cross-sectional shape changes from the circular cross-sectional shape to the elliptical cross-sectional shape, Indicating a tendency to lower. In the case of the drag coefficient, the drag coefficient is theoretically 1 when the pipe 200 has a circular cross-sectional shape.

Therefore, in order to reduce the load acting on the pump tower 100, it is advantageous that the shape of the pipe 200 installed in the pump tower 100 is formed into an elliptical cross-sectional shape.

On the other hand, when the pipe 200 is formed in an elliptic shape having a low drag coefficient, the section modulus is reduced to reduce the bending moment received by the pump tower 100. In order to overcome such a structural stiffness change It is necessary to increase the stiffness of the structure in such a way as to favor the geometrical characteristics or to enhance the quality of the material.

For this, in the embodiment of the present invention, it is preferable that a stiffener 600 passing through the center of the pipe 200 is installed inside the pipe 200. The stiffener 600 is structurally poor in rigidity It is more preferable to be provided on the inner surface of the pipe 200 having the shortest diameter.

Since the reinforcing material 600 has a function of uniformly distributing the load distribution of the pump tower 100 because the load is divided and transmitted, the maximum stress that can be generated according to the design can be reduced, Thereby contributing to an increase in fatigue life.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It should be understood that various modifications made by the person skilled in the art are also within the scope of protection of the present invention.

100: Pump tower 200: Piping
210: supply pipe 220: discharge pipe
230: emergency tube 300: ladder
400: foot plate 500: connecting member
600: Stiffener

Claims (3)

A supply pipe for supplying LNG into the storage tank; a pair of discharge pipes for discharging the LNG stored in the storage tank to the outside; and a main pump connected to the discharge pipe for supplying LNG to the discharge pipe, Wherein the pipeline comprises an emergency pipe for discharging the LNG stored in the tank to the outside, and the pipe structure has an elliptical cross-sectional shape elongated in the width direction of the ship.
The method according to claim 1,
And a reinforcing member passing through the center of the pipe is installed inside the pipe.
3. The method of claim 2,
Wherein the reinforcing member is installed on the inner surface of the pipe having the shortest diameter.

KR1020130154888A 2013-12-12 2013-12-12 Pump tower structure of lng cargo tank KR20150069084A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020130154888A KR20150069084A (en) 2013-12-12 2013-12-12 Pump tower structure of lng cargo tank

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020130154888A KR20150069084A (en) 2013-12-12 2013-12-12 Pump tower structure of lng cargo tank

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20180049990A (en) 2016-11-04 2018-05-14 대우조선해양 주식회사 Pump tower of lng storage tank
KR20180049991A (en) 2016-11-04 2018-05-14 대우조선해양 주식회사 Pump tower of lng storage tank and operating method of this at emergency time
KR20180061943A (en) 2016-11-30 2018-06-08 대우조선해양 주식회사 Discharge pipe connecting apparatus for pump tower of liquid cargo
KR20180076914A (en) 2016-12-28 2018-07-06 대우조선해양 주식회사 Reinforcement apparatus for filling pipe of pump tower in lng cargo tank
KR20180076915A (en) 2016-12-28 2018-07-06 대우조선해양 주식회사 Pump tower in lng cargo tank
KR20180002326U (en) 2017-01-23 2018-08-01 대우조선해양 주식회사 Pump tower in lng cargo tank
CN112498619A (en) * 2020-12-09 2021-03-16 江南造船(集团)有限责任公司 Mounting method of pump tower triangular mast of MARK-III type containment system

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20180049990A (en) 2016-11-04 2018-05-14 대우조선해양 주식회사 Pump tower of lng storage tank
KR20180049991A (en) 2016-11-04 2018-05-14 대우조선해양 주식회사 Pump tower of lng storage tank and operating method of this at emergency time
KR20180061943A (en) 2016-11-30 2018-06-08 대우조선해양 주식회사 Discharge pipe connecting apparatus for pump tower of liquid cargo
KR20180076914A (en) 2016-12-28 2018-07-06 대우조선해양 주식회사 Reinforcement apparatus for filling pipe of pump tower in lng cargo tank
KR20180076915A (en) 2016-12-28 2018-07-06 대우조선해양 주식회사 Pump tower in lng cargo tank
KR20180002326U (en) 2017-01-23 2018-08-01 대우조선해양 주식회사 Pump tower in lng cargo tank
CN112498619A (en) * 2020-12-09 2021-03-16 江南造船(集团)有限责任公司 Mounting method of pump tower triangular mast of MARK-III type containment system

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